1. Field of the Invention
The present invention relates to input apparatuses and image forming apparatuses, and more particularly to an input apparatus that is used when a user inputs an instruction into a main apparatus. The present invention also relates to an image forming apparatus equipped with the input apparatus.
2. Description of the Related Art
An image forming apparatus, such as a copy machine or a printer, typically has an operating panel with a display unit. The display unit may display plural input keys that a user can use to enter an instruction for executing a job. The display unit may also display various other information, such as a status of the image forming apparatus or various messages to the user.
For example, Japanese Laid-Open Patent Application No. 2005-010394 discloses an image forming apparatus that determines an optimum operation position based on physical information about the user, such as his or her height or the use of a wheelchair. In this technology, the height of an operating unit including an operating panel and the height of the ejected-sheet tray are increased or decreased in a linked manner. However, because the image forming apparatus employs mechanical keys, those keys that are frequently used are liable to fail, in which case the entire operating panel needs to be replaced.
Japanese Laid-Open Patent Application No. 2007-219966 discloses a projection input apparatus capable of projecting a keyboard with an appropriate size under different conditions, such as the projected distance. The publication also discloses an information terminal equipped with such projection input apparatus. However, many of the modern image forming apparatuses have multiple functions and offer a wide variety of input items (input menu). Thus, the use of the projection input apparatus with the latest image forming apparatus leads to reduced operability.